Childless Couples Have Higher Death Rates and Mental Illness!!??!!

I hate scientific studies that don't investigate the assumptions on which they're based.  They do harm.  The findings slither around and get into the heads of people who treat people for the issues the research purports to understand.  And the misconceptions become protocol.  Here's one example.

The Journal of Epidemiology and Community Health published an article declaring a connection between childlessness and increased risk of death and mental illness.

Among the findings:

• Having a child cuts the risk of early death, particularly among women.
• The early death rate from circulatory disease, cancers, and accidents among childless women was four times as high as that among those who gave birth to their own child, and 50% lower among women who adopted.
• Similarly, rates of death were around twice as high among men who did not become parents, either biologically or through adoption.
• The prevalence of mental illness in couples who adopted kids was around half that of other parents.

What the study states but doesn't investigate is that for their research they used:  "population-based health and social registers, we conducted a follow-up study of 21 276 childless couples in in vitro fertility treatment."

Do you hear the sound of "WHAT!??!" beginning to reverberate?

Might it be that couples who have been living in the infertility system for months, maybe years and have had their original life script expectations erased, have had doctors and drugs and timetables invade their intimate time, have spent gobs of money, and have had repeated cycles of devastating disappointment may be in a very different state than couples who have CHOSEN not to have children?

And let me state my assumption up front.  Choosing not to have children is not dysfunctional.  It's not a psychological condition.  It's not an ethical/moral lapse.  It's not a sign of immaturity or selfishness.  It's a legitimate choice.

It may be that the researchers' findings do apply to couples who undergo infertility treatment in order to have a child.

But there is harm in assuming that all couples who don't have children are at higher risk for death and mental illness.